Disparity in Rainfall between Pacific Northwest and California

March 26, 2014

The latest Columbia Basin Bulletin reports that the US Army Corps of Engineers is releasing water from the Dworshak Dam to make room for anticipated above average inflows from the spring snow melts, that have already started. The Dworshak Dam is on the north fork of the Clearwater River in west central Idaho and empties into the Snake River just above the big four Lower Snake River Dams. The storage reservoir water level behind the Dworshak Dam rose six feet between March 1st and March 15th. This is good news for migrating salmon and for the hydro power that these dams produce, but bad news for Californians who didn’t get needed water.

Californians continue to look square in the face of a continued and serious drought. On the California Data Exchange Center’s website for March 20th, there is not one reservoir that is 100% full. The range is 21% to 53% of total capacity except Pyramid and Castaic Lakes, which are 86% and 92% respectively. California is nearing the end of its rainy season and there has not been enough rainfall or snow accumulation to fill these reservoirs. From the Klamoth River in the north of the state to the Colorado Desert in the south, the percent of historic average rainfall in each of the 36 measured areas averages about 29%.

NOAA produced a map of recent precipitation in the West, above left. This shows the higher rainfall in the Pacific Northwest and west central Idaho and dry conditions southward. What is more disturbing is the NOAA map showing the precipitation average over the past 3 years, above right. The end is not in sight.

*Posted from San Francisco by Barbara Folger, NWNL Project Coordinator